1. Field of the Invention
The present invention relates to treadmills and more particularly, to a liftable and foldable treadmill that can be lifted to a desired tilting position or folded to a collapsed position.
2. Description of the Related Art
Taiwan Patent Utility M247231 discloses a treadmill in which the running platform is liftable relative to an open frame by a linear brake and a sliding frame set, i.e., the front side of the running platform can be lifted to increase the slope of the running platform. Further, the rear side of the running platform can be lifted to a collapsed erected position, and at the same time, the coupled sliding frame set and a front frame support set can carry two pneumatic cylinders and a support rod to hold the running platform in the collapsed erected position.
The aforesaid running platform lifting mechanism and folding mechanism are complicated. Further, the sliding frame set lifts the running platform by means of stopping against two cushion blocks at the open frame to produce a reaction force. Since the open frame is spaced above the ground at a certain distance, the supporting force provided by the open frame to the running platform is insufficient to protect the running platform from vibration during running of a person on it.